Previous solutions to make inorganic thermoset resins included, for example, contacting potassium silicate solution, water, Al2O3, ZrO2 and kaolin. ZrO2 and kaolin are common fillers in geopolymeric resins. A gel is formed that finally forms the inorganic thermoset resin. Then, metakaolin in powder form is added to the thermoset resin to avoid shrinkage during the resin curing. Dissolution of metakaolin powder is not a straightforward step, since this powder has low solubility. Metakaolin needs to be dissolved for a predetermined period of time. This is a time consuming and expensive step (metakaolin needs to be finely dispersed in the alkaline solution and that involves a complex process using a special mixing apparatus). Moreover, since metakaolin has to be added in a certain % weight of the resin, the addition of metakaolin considerably increases the weight of the resin.
There is a need in the art for an improved method to make fire resistant inorganic thermoset resins which eliminates the step of addition of the anti-shrinkage filler metakaolin, while at the same time provides a fire resistant inorganic thermoset resin which does not shrink during the resin curing.